In the technical field of connectors, particularly in the field of electrical connector plugs, it is necessary to provide a locking device between the connector and a mating socket to prevent disconnection there between as a result of environmental conditions, for example, vibrations, that occur where the connection is made. It is important that the locking device be able to be connected and disconnected quickly and reliably in fields where there are frequent connections and disconnections and, in particular, on removable elements.